**6.4. CYP1A1 and CYP2B in different species after treatment with PAHs**

In Table 4A-B we reported the results of the mean levels of immunofluorescence of CYP1A1 (A) and CYP2B (B), revealed in cultured fibroblasts of different species treated with PAHs, expressed as index numbers.

Only the fibroblasts of some species were treated with PAHs due to the fact that there was not a sufficient amount of cells from all of them to perform the various contaminant treatments. These planar contaminants are known to induce CYP1A1. In fact, an increase of CYP1A1 was detected, at least at one dose, in all specimens cultured fibroblasts exposed to PAHs (Table 4A) (Figure 5A-E). In the Risso's dolphin (GGL1) and in the striped dolphin (RT1), the higher dose of PAHs even caused the death of all cells. The fibroblast vitality was assessed with trypan blue, a quality control test to check the cell preparation. In the event of cell damage, trypan blue penetrates the cell membrane, and dead or damaged cells appear blue [36]. CYP2B also, showed induction in the three species treated with PAHs (Table 4B). The striped dolphin (RT1) showed the same trend for the two cytochromes (Table 4A-B).

60 New Approaches to the Study of Marine Mammals

retardant treatments.

expressed as index numbers.

present in the induction of the two cytochromes.

in killer whale (MOO12) and striped dolphin (RT1), while discontinuous induction responses were showed for CYP1A1 and CYP2B by the other species. Also these contaminants are mainly with globular structure as OC mixture, but no differences are

**Figure 4.** A-D: Immunofluorescence (AUF/nucleus) of CYP1A1 (A-B) and CYP2B (C-D) in fibroblast cells of striped dolphin (RT1) (A, C) and long-beaked common dolphin (MDC12) (B, D) treated with flame retardants. DAPI and Alexa Fluor 594 (Intensity 200ms) images of Nonane and the three flame

In Table 4A-B we reported the results of the mean levels of immunofluorescence of CYP1A1 (A) and CYP2B (B), revealed in cultured fibroblasts of different species treated with PAHs,

Only the fibroblasts of some species were treated with PAHs due to the fact that there was not a sufficient amount of cells from all of them to perform the various contaminant treatments. These planar contaminants are known to induce CYP1A1. In fact, an increase of CYP1A1 was detected, at least at one dose, in all specimens cultured fibroblasts exposed to PAHs (Table 4A) (Figure 5A-E). In the Risso's dolphin (GGL1) and in the striped dolphin (RT1), the higher dose of PAHs even caused the death of all cells. The fibroblast vitality was

**6.4. CYP1A1 and CYP2B in different species after treatment with PAHs** 


**Table 4.** (A-B): Mean values of immunofluorescence of CYP1A1 (A) and CYP2B (B) revealed in cultured fibroblasts of different species treated with PAHs (Dose C = 0.5μM BaP + 10μM BnF, Dose B = 2.5μM BaP + 50μM BnF and Dose A = 12.5μM BaP + 250μM BnF). The immunofluorescence is expressed as index numbers respect to solvent control. Different colour of box is related to different increase of these proteins. N.C. = no cells. D.C. = death cells.
